A U.S.-led plan to let all countries set their own goals for fighting climate change is gaining grudging support at U.N. talks, even though the current level of pledges is far too low to limit rising temperatures substantially.

The approach, being discussed this week at 160-nation talks in Bonn, Germany, would mean abandoning the blueprint of the 1997 Kyoto Protocol, which set central goals for industrialised countries to cut emissions by 2012 and then let each work out national implementation.

Attempts to agree a successor to Kyoto have foundered above all on a failure to agree on the contribution that developing countries should make to curbing the industrial emissions responsible for global warming – greenhouse gases. The next ministerial conference to try to reach a deal is scheduled for Paris in 2015.

The United States, recently overtaken by China as the world’s biggest carbon polluter, never ratified Kyoto because it set no binding emissions cuts for rapidly growing economies such as China and India.

President Barack Obama’s administration now says each nation should define its “contribution” to a new U.N. accord – a weaker word than past U.S. demands for national “commitments”.